The negative number shows how much has to be risked to win aR$100 payout. Thus, if the money line for the team that you picked was -400, it means that if you placed a successfulR$400 bet, you would gainR$100 on payout.
Moneyline betting is where you pick the winner of an event or game. Negative odds indicate favorites, and underdogs have positive odds. The range between the odds can indicate the closeness of the matchup in the eyes of the sportsbook.